<div class="grid-item" (click)="action.emit()">
  <button
    [ngStyle]="{ opacity: value() !== null ? 1 : 0, transition: 'all .1s ease-in-out' }"
    [disabled]="disabled()"
  >
    {{ value() !== null ? (value() == 1 ? 'X' : 'O') : 'X' }}
  </button>
</div>
